The substituted heterocycle fused gamma-carbolines lumateperone (4-((6bR,10aS)-3-methyl-2,3,6b,9,10,10a-hexahydro-1H-pyrido[3′,4′: 4,5]pyrrolo[1,2,3-de]quinoxalin-8(7H)-yl)-1-(4-fluorophenyl)-1-butanone) is known to be a serotonin receptor (5-HT2A), dopamine receptor (D1 and/or D2), and serotonin transporter (SERT) ligand, which is useful in treating a variety of central nervous system disorders.
Lumateperone antagonizes the serotonin-2A (5-HT2A) receptor, and/or modulates dopamine receptor signaling at the level of key intra-cellular phosphoproteins. This compound is principally known to be useful for the treatment of positive and negative symptoms of schizophrenia, depression (especially acute depression and bipolar depression), anxiety and traumatic disorders (including acute anxiety and post-traumatic stress disorder), and dementias (including Alzheimer's disease and the symptoms associated therewith). At dopamine D2 receptors, this compound has dual properties and acts as both a post-synaptic antagonist and a pre-synaptic partial agonist of the D2 receptor. It also stimulates phosphorylation of glutamatergic NMDA NR2B, or GluN2B, receptors in a mesolimbic specific manner. It is believed that this regional selectivity in the brain areas thought to mediate the efficacy of antipsychotic drugs, together with the serotonergic, glutamatergic, and dopaminergic interactions, may result in antipsychotic efficacy for positive, negative, affective and cognitive symptoms associated with schizophrenia. The compound also exhibits serotonin reuptake inhibition, providing antidepressant activity for the treatment of schizoaffective disorder, co-morbid depression, and/or as a stand-alone treatment for major depressive disorder. Lumateperone is also useful for the treatment of bipolar disorder and other psychiatric and neurodegenerative disorders, particularly behavioral disturbances associated with dementia, autism and other CNS diseases. These features may be able to improve the quality of life of patients with schizophrenia and enhance social function to allow them to more fully integrate into their families and their workplace. Lumateperone displays differential dose-dependent effects, selectively targeting the 5-HT2A receptor at low doses, while progressively interacting with the D2 receptor at higher doses. As a result, at lower doses, it is useful in treating sleep, aggression and agitation. At a high dose, it can treat acute exacerbated and residual schizophrenia, bipolar disorders, and mood disorders.
Lumateperone, having the formula:
is a novel therapeutic agent with potent (Ki=0.5 nM) 5-HT2A receptor antagonism, activity as a mesolimbic/mesocortical-selective dopamine receptor protein phosphorylation modulator consistent with presynaptic D2 receptor partial agonism and postsynaptic D2 receptor antagonism (Ki=32 nM) in vivo, high D1 receptor affinity (Ki=52 nM), and inhibition of the serotonin transporter (SERT) (Ki=26-62 nM, using different assays for SERT activity). Lumateperone is in Phase III clinical development as a treatment for schizophrenia, bipolar depression and agitation in dementia, including Alzheimer's Disease.
Lumateperone and related compounds have been disclosed in U.S. Pat. Nos. 6,548,493; 7,238,690; 6,552,017; 6,713,471; U.S. RE39,680, and U.S. RE39,679, as novel compounds useful for the treatment of disorders associated with 5-HT2A receptor modulation such as anxiety, depression, psychosis, schizophrenia, sleep disorders, sexual disorders, migraine, conditions associated with cephalic pain, and social phobias. U.S. Pat. Nos. 7,081,455 and 8,309,722 also disclose methods of making substituted heterocycle fused gamma-carbolines and uses of these gamma-carbolines as serotonin agonists and antagonists useful for the control and prevention of central nervous system disorders such as addictive behavior and sleep disorders. U.S. Pat. No. 8,598,119 and U.S. 2015/0080404, each incorporated herein by reference, disclose the use of specific substituted heterocycle fused gamma-carbolines for the treatment of a combination of psychosis and depressive disorders as well as sleep, depressive and/or mood disorders in patients with psychosis or Parkinson's disease and for the treatment or prophylaxis of disorders associated with dementia, particularly behavioral or mood disturbances such as agitation, irritation, aggressive/assaultive behavior, anger, physical or emotional outbursts and psychosis and sleep disorders associated with dementia. U.S. Pat. No. 8,648,077, incorporated herein by reference, discloses methods of preparing toluenesulfonic acid addition salt crystals of particular substituted heterocycle fused gamma-carbolines, e.g., toluenesulfonic acid addition salt of 4-((6bR,10aS)-3-methyl-2,3,6b,9,10,10a-hexahydro-1H-pyrido[3′,4′: 4,5]pyrrolo[1,2,3-de]quinoxalin-8(7H)-yl)-1-(4-fluorophenyl)-1-butanone.
U.S. Pat. No. 8,993,572, incorporated herein by reference, discloses prodrugs/metabolites of substituted heterocycle fused gamma-carboline for improved formulation, e.g., extended/controlled release formulation. This application discloses that heterocycle fused gamma-carboline N-substituted with a 4-fluorophenyl(4-hydroxy)butyl moiety are shown to have high selectivity for the serotonin transporter (SERT) relative to the heterocycle fused gamma-carboline containing 4-fluorophenylbutanone.
U.S. Pat. No. 8,598,119 teaches that selected substituted heterocycle fused gamma-carboline compounds have nanomolar affinity for the serotonin reuptake transporter (SERT) and so are selective serotonin reuptake inhibitors.
It has also recently been found that lumateperone may be particularly effective in treating acute depression and acute anxiety owing to its rapid onset of action compared to existing antidepressants. This is believed to be due to its signaling through a neurotransmitter system separate from the traditional monoamine signaling systems. Lumateperone provides a dopamine D1 receptor-dependent enhancement of NMDA and AMPA currents coupled with activation of the mTOR (e.g., mTORC1) signaling pathway.